Have you noticed the futuristic looking cars, with the steeply sloping
hood and blunt tail, quietly moving around your community?
They are
Toyota Priuses, which are hybrid cars with power supplied by both a gasoline
engine and on electric motor. (Be careful when you are around one when it is
backing or starting forward slowly, because only the quiet electric motor is
providing the power then.)
20,000 Toyota Priuses were sold in the
United States in 2003. Plans are that 100,000 will be sold in the U.S. in 2005.
(There are other hybrid vehicles on the streets; for example, the Honda Insight
and Civic and Accord, the Ford Escape SUV, which uses the Toyota hybrid system,
and the Toyota Highlander SUV.) It will be a major event next year when the
Toyota Camry, the top selling car in the U.S., becomes hybrid.
The
word "Prius" means "forerunner". The name is apt because hybrid cars are the
first "baby step" toward freeing the U.S. transportation system from dependency
on imported gasoline and reducing greenhouse-gas emission from vehicles.
Why is the U.S. so dependent on foreign imports of petroleum to make
gasoline? It's because the U. S. peaked in petroleum production in the early
1970s and is now almost halfway down the production curve. (The "Energy Crisis"
of the early 1970s was due to that fact. We then switched into import mode in a
big way, mostly from the Middle East.) Alaska oil was a small blip on the
production curve; and any further Alaska oil will be an even smaller blip.
And, if running out of oil is not bad enough, the vehicle emissions as a
result of using petroleum fuels in vehicles is a major cause of global warming.
Global warming may cause the next-major ice age to occur much sooner than it
would without global warning.
Ok, you say, we'll just continue
importing oil to meet our needs. Not for long! For one thing, other countries,
such as the huge-population countries India and China, are greatly increasing
their imports. But, more importantly, world oil production is peaking now or in
the very near future. If you thought the "U.S Energy Crisis" of the 1970s was
bad, just wait until you experience the "World Energy Crisis" of the 2000s!
In the March 2005 issue of Scientific American Professor Emeritus
William Ruddiman of University of Virginia showed that the advent of
agriculture replacing hunting and gathering for human food caused enough global
warming to keep the next 100,000-year major ice age from starting a few
thousand years ago. About 8,000 years ago carbon dioxide in the upper
atmosphere started rising instead of falling as it would have without the
effects of farming. Then about 5,000 years ago methane gas, an even more
effective greenhouse gas than carbon dioxide, began rising instead of falling
as it would have without the effects of extension flooding of land for rice
farming in most of Asia. Both of these greenhouse gases kept world temperature
from falling rapidly.
Then, of course, fossil fuels were discovered and
widely used, which caused world temperature to start rising rapidly in a
tightly coupled race with rising world population. Within about 1,000 years all
fossil fuels will have peaked in world production, and humans will have to deal
with the down slope of the production curve of the remaining coal. Petroleum
will have been long gone by then.
If the past is a predictor of the
future, humans will accelerate their use of fossil fuels, especially coal and
other really bad polluters to keep increasing in energy use. Such use will
cause world temperatures to rise even faster.
Well, you say, that is
great! Global warming has kept a really cold ice age from starting. Whoa! Did
you see the movie "The Day After Tomorrow"? It had some good climate science in
it, except for the really fast time scale of weeks to months instead of decades
to centuries. A major fear of climatologists is that extreme global warming
will cut off the crucial Atlantic current, that brings warm water from the
equator to the North Atlantic, sooner than it would normally cut off with the
long-term steady global warming caused by pre-modern agriculture. (That was the
main thesis of the movie.) Without that steady global warming the Atlantic
current would have already cut off. The global warming of pre-modern
agriculture is what has caused the unusual length (about 10,000 years) of the
present interglacial.
When the Atlantic current is cut off, the entire
world geography of agriculture will drastically change. Those areas, such as
the U.S., where agriculture is now so intensive will lose some or, maybe much,
of that capability, while other areas of the world will gain the capability to
produce food. Perhaps northern Canada and Siberia will become the breadbaskets
of the world. Needless to say, much disruption of current economic relations
among the nations of the world will occur.
What do humans do when they
realize that their source of food and energy is being jeopardized? History
tells us that they fight ferociously to preserve what they have or to gain
more, often killing millions in the fight. That is what is really scary! Many
nations of the world, especially the U.S., have many nuclear weapons already
aimed at other nations. Do you think that they will not use them if their land
or sources of food and energy are threatened? The U.S. has already set the
precedence for doing so in Japan in 1945.
So, there are many things
that the world must do to prepare for the troubled times ahead. Certainly,
proceeding as usual will not work. All of the action items will require a high
degree of cooperation of all nations of the world, not a go-it-alone attitude
of any one nation. Here are some action items that are definitely needed:
So how does one get from this gloomy picture of the future to the
importance of putting more hybrid vehicles on our highways? As stated above, it
is a first "baby step". Hybrid cars get about double the gasoline mileage of
the average car and reduce emissions by huge amounts. Within a decade hybrid
vehicles will be the dominant mode of new vehicles for highway
transportation.
The next baby step will be "plugable" or "gridable"
hybrid vehicles, a hybrid vehicle with a more powerful battery that can be
plugged into the national electric grid. Such a vehicle can travel about thirty
miles, less than a typical local trip, on electricity without using its
gasoline engine, thus doubling its gasoline mileage and halving its emissions.
(Emissions at a power plant can be more easily controlled than emissions at the
point of use of each vehicle.)
Another possible baby step might be to
use recycled vegetable oils as the fuel for hybrid cars instead of gasoline.
Specifically producing fuels by agriculture often uses more energy than can be
gotten from the produced fuels. However, by recycling oils the energy use in
processing can be greatly reduced.
Oh, you say, we will use hydrogen
fuel cell vehicles. We may use such vehicles in the future, but they will not
solve most of our problems and may cause more problems. Electricity has to be
used to produce the hydrogen, which has to produced by some energy source;
i.e., coal or nuclear reactions. Huge amounts of infrastructure have to be
built to handle hydrogen as a vehicle fuel. Hydrogen is difficult to store and
can be dangerous to handle, although perhaps not more dangerous than
gasoline.
Has anyone thought of what happens to all the water hydrogen
vehicles will dump on the roads? Will there be clouds over the highways and
layers of ice in winter? Water vapor put into the atmosphere is a potent
greenhouse gas. Will vehicles have to carry huge amounts of water around to be
dumped at hydrogen refueling stations?
These problems with using
hydrogen in vehicles makes me believe that it would be better to have hydrogen
fuel cells in garages and other specific locations rather than in vehicles.
Then the localized water produced could be used to alleviate lack of clean
water. The electricity produced at those specific locations could be used to
power the location, to recycle vegetable oil for fuel and to be put into the
national grid for charging plugable hybrid cars at their storing locations.
Solar cells at the locations could be used to harness solar energy for
producing electricity, part of which can be use to make hydrogen and part can
be fed into the national electric grid.
All of the above problems with
vehicle fuels makes it obvious that trains need to come back as a major mode of
transportation in the U.S. as they are in many other places because train
transportation is more energy efficient.
We need a long-view system
approach to transportation and other types of infrastructure to get humans
through the transition into the era of declining fossil fuel use and into the
next 100,000-year major ice age.
So, when you see one of those
futuristic hybrid cars on the streets, you might want to applaud; or go buy one
for yourself.
L. David Roper, 1001 Auburn Dr. SW, Blacksburg VA 24060-8123
Prof.
Emeritus of Physics, Va. Poly. Inst. and State Univ.
roperld@vt.edu